Am.  Jour.  Pharm.  \ 
November,  1897.  J 
Official .  Lead  Preparations-. 
565 
As  a  necessary  consequence,  decrease  both  in  specific  gravity  and 
volumetric  strength  will  result. 
This  was  noticed  by  Prof.  J.  U.  Lloyd  in  a  paper  published  in  the 
American  Journal  of  Pharmacy,  and  in  a  number  of  observations 
the  writer  can  only  record  a  similar  experience. 
SPECIFIC  GRAVITY  OF  GOULARD'S  EXTRACT. 
The  specific  gravity  of  commercial  Goulard's  extract  varies 
widely. 
One  sample,  which  was  stated  to  be  of  recent  preparation,  had  a 
specific  gravity  of  1-270,  and  13-67  grammes  required  between  29 
and  30  c.c.  of     sulphuric  acid  for  precipitation. 
This  specimen  was  evidently  prepared  according  to  the  Pharma- 
copoeia of  1870. 
On  the  other  hand,  one  solution  was  found  of  the  specific  gravity 
of  1-128,  which  required  only  15  c.c.  of  the  normal  acid  for  the  pre- 
cipitation of  13-67  grammes. 
This  preparation  was  cloudy,  and  bore  evidence  of  careless 
preservation. 
The  present  Pharmacopoeia  states  the  specific  gravity  to  be  about 
1-195,  while  the  edition  of  1880  requests  the  same  to  be  1-228. 
The  latter  employs  a  larger  quantity  of  lead  oxide,  but  both  are 
unanimous  in  the  amount  of  basic  salt,  each  demanding  25  per 
cent. 
A  number  of  determinations  have  led  the  writer  to  the  conclu- 
sion that  the  specific  gravity  point  of  the  present  Pharmacopoeia  is 
placed  too  low. 
This  was  first  suggested  while  examining  a  commercial  speci- 
men, which  possessed  the  specific  gravity  of  1-1875,  Dut  only 
required  20  c.c.  of  normal  sulphuric  acid  for  precipitation  of  13  67 
grammes. 
Several  samples,  with  specific  gravities  closely  approximating  the 
official  figure,  were  invariably  found  to  require  less  than  25  c.c.  of 
the  normal  acid  for  precipitation. 
It  was  also  found  that  considerable  variation  in  specific  gravity 
took  place  if  lead  acetate  was  employed  obtained  from  different 
sources. 
It  was,  in  fact,  found  impossible  to  purchase  this  salt  in  the  mar- 
